Figure 2: Average classification accuracy rates when FLD classifier is used only (cyan plots) and when a feature extraction method plus FLD classifier is used for 100 Monte Carlo simulations. The considered different types of feature extraction methods are PCA (blue plots), STIWK PCA (green plots), MTIWK PCA (red plots), and MDWK PCA (black plots) for the data simulated with different values of 𝜎𝑥.